Per arvid peterson



INVENTOR. M w...

A TTORN E Y UNITED STATES PATENT OFFICE.

PER ARVID PETERSON, OF TRENTON, NEW JERSEY, ASSIGNOR TO DE LAVAL STEAM TURBINE COMPANY, OF TRENTON, NEW JERSEY, A. CORPORATION OF NEW JERSEY.

FLEXIBLE GEAR-WHEEL.

Specification of Letters Patent.

Patented Aug. 5, 1919.

Application filed September 17, 1918. Serial No. 254,400.

To all whom it may concern:

Be itknown that I, PER ARVID PETERSON, a citizen of the United States of America, and a resident of Trenton, county of'Mercer, and State of New Jersey, have invented new and useful Improvements in Flexible Gear- Wheels, of which the following is a specificat'ion.

My invention relates to flexible gears or gear wheels; by which term is meant, gear wheels composed of laminae so held that they may accommodate themselves to imperfections or distortions of another gear, pinion, or rack with which such flexible gear ma be in engagement. The gear herein descrlbed is particularly intended for use in the transmission of large power and for intermeshing with a small pinion. It has been found that there is difficulty in transmitting large powers between small pinions and lar e gears, the latter being rigid; under load, tl e pinion will deflect or distort more in its eendisk or hub, by a flexible pin,

ter than at or near its ends, owing to the existing bending and torsional stresses; and, other things being equal, the smaller the pinion the greater will be the deflection and distortion. The result of the deflection or distortion is heavy bearing on the extreme ends of the teeth.- In the case of a spiral gear and pinion, heavy bearing will occur on the pinion at the extreme end of the helix or helices.

According to the present invention these difiiculties are overcome and compensated for automatically. The ear is composed of a number of laminae, he d to a central hub by pins or bolts the length of which increases progressively according to the distance of the corresponding laminae from the said central hub; as a result, in action the laminae nearest the central hub experience minimum deflection 'in the direction of rotation, the deflection of other laminae more distant from the central hub being pro essively greater. Proper proportioning o the .pins or bolts to the conditions of use will result in practically uniform. ressure along the faces of the teeth, notwit standing considerable distortion of the pinion.

My invention thereforecomprises a structure wherein a number of laminae are each connected to a common and relatively fixed in such manner that each lamina may yield individually to pressure; other features of my invention will be pointed out hereinafter. The object of my invention is to improve the construction of flexible gears, such as referred to.

I will now proceed to describe my invention with reference to the accom anying drawing,in which one construction 0 flexible gear embodying my invention is illustrated, and will then point out the novel features in claims. In said drawing:

Figure 1 shows an axial section of a gear wheel constructed in accordance with my invention, and Fig. 2 shows an end elevation thereof.

In said figures, numeral 1 designates the said central hub or disk, having two sleevelike portions on opposite sides of its central disk 2, upon which sleeve-like portions are mounted the gear-toothed disks or laminae 3. In the construction shown, the laminae on each side of this central disk are equal in number.

From this central disk 2 bolts 4, 4,-4, of progressively varying lengths such that each group of such pins, 4, or 4, or 4, etc., serves for one disk or lamina, or one pair of disks or laminae, only, passing, with considerable clearance, through intermediate .laminee. Thus, the pins marked 4 connect the two outer laminae to the central disk 2; the pins marked 4? connect those laminae lying next to the outer laminae, to the central disk 2; and so on. Each pin, other than the shortest pins, 4, passes through intermediate laminae with such clearance as permits its flexure to the required extent. The pins are provided on their ends with suitable screw nuts, whereby project pins or the disks or laminae which they serve are secured to them, and so to the central hub and disk 1-2. p

5 designates a shaft upon which the huh I is mounted, and 6 a ke by which the hub is secured to said she. It will be apparent that in the event of transmission of power from or to shaft 5, through the laminated gear, and through a pinion in mesh with that gear, the laminae of the gear may yield as may be necessary to compensate for bending or other distortion of the pinion; such yielding being affected by slight backnecting such laminae individually to said support and adapted by flexure to permit individual yielding of the laminae, the pins for outer lam'inae j passing with clearance through apertures in the lamina or laminae intermediate such outer laminae and the suport. p 2. A flexible gear comprising a'plurality of laminae, a support comprising a hub upon which said laminae are mounted, and a disk forming 'a part of said hub and separating the lamina or said laminae into a plurality of groups, and flexible pins projecting laterally from said disk and each connecting one or more said laminae individually to said disk and adapted by flexure to permit individual yielding of the laminae, the pins for outer laminae passing withclearance through apertures in laminae intermediate such outer laminae and the support.

In testimony whereof I have signed this specification in the presence of'two subscribing witnesses.

PER ,ARVID PETERSON.

Witnesses:

'C. R. War um, C. J. ALBmm. 

